Modern vehicles are frequently equipped with multi-speed, dual-clutch transmissions (DCT) as part of the subject vehicle's powertrain. Such DCTs are favored for their increased mechanical efficiency in comparison with typical, torque-converter equipped automatic transmissions. Additionally, multi-speed, dual-clutch transmissions are often preferred over typical automated manual transmissions for the DCT's capability to provide higher quality gear shifts.
A typical DCT employs two friction clutches for shifting among its forward ratios, and accomplishes such shifts by alternating engagement between one and the other of the two friction clutches. Such a multi-speed, dual-clutch transmission may be utilized in a hybrid vehicle, i.e., a vehicle employing two or more distinct power sources, such as an engine and an electric motor, for transmitting propulsion energy to subject vehicle's driven wheels.
During operation of a vehicle, significant amount of heat or thermal loads may be generated by and transferred to various subsystems of the powertrain, including the employed DCT. When such thermal loads exceed specific thresholds, performance and reliability of the DCT, as well as general performance of the vehicle, may be adversely affected.